| Abstract: | Feline bone marrow cells were separated based on their density distribution in a continuous polyvinyl-pyrrolidone-coated silica gel density gradient. Morphologic identification of cytocentrifuged preparations at specific densities revealed a progressive increase in density with maturation of the cells within the granulocytic and erythroid series. Segmented eosinophils peaked at 1.084 g/ml, monocytes at 1.07 g/ml, and lymphocytes spanned the density of 1.068 to 1.084 g/ml. Bone marrow samples from 6 healthy specific-pathogen-free cats were separated by the continuous polyvinyl-pyrrolidone-coated silica gel gradient and were studied for progenitor colony formation in methylcellulose. Erythroid colony formation was greatest at a density of 1.084 g/ml and also appeared in cells from 4 cats at a lighter density of 1.016 to 1.05 g/ml. Colony formation in the granulocytic series revealed progenitors throughout the gradient with enrichment at 1.055 g/ml. |
